1. Field of the Invention
The present invention relates to a word processing system, more particularly, to a word processing system for inserting characters into a series of characters positioned within a predetermined field and displayed on a display unit.
2. Description of the Prior Art
The development of word processing has made possible electronic card systems in which information is stored on card images in a floppy disk or other memory medium, thereby enhancing office efficiency. In such a system, a card image, i.e., a field, is displayed on a display unit and information is added thereon. It should be noted that the area of each field is predetermined by defining the start coordinates, the number of rows, the number of columns, and the like. Accordingly, the number of characters to be written into each field is limited.
In a Japanese language word processing system, "hiragana"-to-"kanji" transformation is carried out, that is, words are typed in by phonetic "hiragana" (synbols in a cursive syllabary) and then, when necessary, transformed into the corresponding ideographic "kanji" characters.
In this Japanese language word processing system, when characters are inserted into a series of displayed characters, the characters displayed after the inserted characters must be shifted forward. In addition, when a "hiragana"-to-"kanji" transformation is performed, the characters displayed after the transformed "hiragana" may have to be shifted backward depending on whether the character length of the "kanji" is shorter than that of the "hiragana".
As a result of continual forward and backward shifting, the characters on the display become difficult to observe.
To keep the displayed characters from being continuously visually shifted in forward and backward, a prior art method is known in which the series of characters displayed on and after a displayed cursor temporarily disappear from the display when a key indicating a character insertion is pushed and then the series is redisplayed and combined with the end of the inserted characters when an execution key is pushed after the completion of character insertion.
When the above-mentioned prior art method is applied to a word processing system using a predetermined field (or card image), however, there is the disadvantage that, after character insertion, some of the characters which are temporarily erased from the display may overflow the available space in the field and accordingly may be inadvertently lost.